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Review of the Geology and Paleontology of the Ellsworth Mountains, Antarctica
U.S. Geological Survey and The National Academies; USGS OF-2007-1047, Short Research Paper 107; doi:10.3133/of2007-1047.srp107 Review of the geology and paleontology of the Ellsworth Mountains, Antarctica G.F. Webers¹ and J.F. Splettstoesser² ¹Department of Geology, Macalester College, St. Paul, MN 55108, USA ([email protected]) ²P.O. Box 515, Waconia, MN 55387, USA ([email protected]) Abstract The geology of the Ellsworth Mountains has become known in detail only within the past 40-45 years, and the wealth of paleontologic information within the past 25 years. The mountains are an anomaly, structurally speaking, occurring at right angles to the Transantarctic Mountains, implying a crustal plate rotation to reach the present location. Paleontologic affinities with other parts of Gondwanaland are evident, with nearly 150 fossil species ranging in age from Early Cambrian to Permian, with the majority from the Heritage Range. Trilobites and mollusks comprise most of the fauna discovered and identified, including many new genera and species. A Glossopteris flora of Permian age provides a comparison with other Gondwana floras of similar age. The quartzitic rocks that form much of the Sentinel Range have been sculpted by glacial erosion into spectacular alpine topography, resulting in eight of the highest peaks in Antarctica. Citation: Webers, G.F., and J.F. Splettstoesser (2007), Review of the geology and paleontology of the Ellsworth Mountains, Antarctica, in Antarctica: A Keystone in a Changing World – Online Proceedings of the 10th ISAES, edited by A.K. Cooper and C.R. Raymond et al., USGS Open- File Report 2007-1047, Short Research Paper 107, 5 p.; doi:10.3133/of2007-1047.srp107 Introduction The Ellsworth Mountains are located in West Antarctica (Figure 1) with dimensions of approximately 350 km long and 80 km wide. -
The Paleoecology and Biogeography of Ordovician Edrioasteroids
University of Tennessee, Knoxville TRACE: Tennessee Research and Creative Exchange Doctoral Dissertations Graduate School 8-2011 The Paleoecology and Biogeography of Ordovician Edrioasteroids Rene Anne Lewis University of Tennessee - Knoxville, [email protected] Follow this and additional works at: https://trace.tennessee.edu/utk_graddiss Part of the Paleontology Commons Recommended Citation Lewis, Rene Anne, "The Paleoecology and Biogeography of Ordovician Edrioasteroids. " PhD diss., University of Tennessee, 2011. https://trace.tennessee.edu/utk_graddiss/1094 This Dissertation is brought to you for free and open access by the Graduate School at TRACE: Tennessee Research and Creative Exchange. It has been accepted for inclusion in Doctoral Dissertations by an authorized administrator of TRACE: Tennessee Research and Creative Exchange. For more information, please contact [email protected]. To the Graduate Council: I am submitting herewith a dissertation written by Rene Anne Lewis entitled "The Paleoecology and Biogeography of Ordovician Edrioasteroids." I have examined the final electronic copy of this dissertation for form and content and recommend that it be accepted in partial fulfillment of the requirements for the degree of Doctor of Philosophy, with a major in Geology. Michael L. McKinney, Major Professor We have read this dissertation and recommend its acceptance: Colin D. Sumrall, Linda C. Kah, Arthur C. Echternacht Accepted for the Council: Carolyn R. Hodges Vice Provost and Dean of the Graduate School (Original signatures are on file with official studentecor r ds.) THE PALEOECOLOGY AND BIOGEOGRAPHY OF ORDOVICIAN EDRIOASTEROIDS A Dissertation Presented for the Doctor of Philosophy Degree The University of Tennessee, Knoxville René Anne Lewis August 2011 Copyright © 2011 by René Anne Lewis All rights reserved. -
Nautiloid Shell Morphology
MEMOIR 13 Nautiloid Shell Morphology By ROUSSEAU H. FLOWER STATEBUREAUOFMINESANDMINERALRESOURCES NEWMEXICOINSTITUTEOFMININGANDTECHNOLOGY CAMPUSSTATION SOCORRO, NEWMEXICO MEMOIR 13 Nautiloid Shell Morphology By ROUSSEAU H. FLOIVER 1964 STATEBUREAUOFMINESANDMINERALRESOURCES NEWMEXICOINSTITUTEOFMININGANDTECHNOLOGY CAMPUSSTATION SOCORRO, NEWMEXICO NEW MEXICO INSTITUTE OF MINING & TECHNOLOGY E. J. Workman, President STATE BUREAU OF MINES AND MINERAL RESOURCES Alvin J. Thompson, Director THE REGENTS MEMBERS EXOFFICIO THEHONORABLEJACKM.CAMPBELL ................................ Governor of New Mexico LEONARDDELAY() ................................................... Superintendent of Public Instruction APPOINTEDMEMBERS WILLIAM G. ABBOTT ................................ ................................ ............................... Hobbs EUGENE L. COULSON, M.D ................................................................. Socorro THOMASM.CRAMER ................................ ................................ ................... Carlsbad EVA M. LARRAZOLO (Mrs. Paul F.) ................................................. Albuquerque RICHARDM.ZIMMERLY ................................ ................................ ....... Socorro Published February 1 o, 1964 For Sale by the New Mexico Bureau of Mines & Mineral Resources Campus Station, Socorro, N. Mex.—Price $2.50 Contents Page ABSTRACT ....................................................................................................................................................... 1 INTRODUCTION -
Monoplacophoran Limpet
16 McLean: Monoplacophoran Limpet FIGURES 17-21. Neopilinid radular ribbons, magnifications adjusted to show a similar number of teeth rows. FIGURE 17, Vema (Vema) ewingi. intact ribbon with teeth aligned (LACM 65-11, 6200 m. 110 mi. W of Callao. Pern. R/V ANTON BRUUN, 24 November 1965). FIGURE 18, Vema (Vema) ewingi. another portion of same ribbon with lateral teeth turned to the side. FIGURE 19. Neopilina veleronis. intact ribbon of paratype, teeth not aligned (AHF 603, 2730-2769 m, 30 mi. W of Natividad Island. Baja California, Mexico). FIGURE 20, Vema (Laevipilina) hyalina new species, intact ribbon with teeth aligned, focused on shafts of lateral teeth (LACM 19148). FIGURE 21, Vema (Laevipilina) hyalina, same ribbon, focused on fringe of first marginal teeth. instead of the highly reduced condition in these two species. Al- small-sized species have similar teeth. Radular differences among though the first lateral of N. veleronis is somewhat larger than it the species examined are quantitative rather than qualitative, sup- is in the other two species, that of V. hyalina is still the larger. porting placement of the four species in the same family. A study The fringed first marginal of V. hyalina is much broader than in of the radulae of the other three living species of neopilinids N. veleronis. Only in V. hyalina is the fringed tooth so broad that should reveal further specific differences. it overlaps the opposite member in the central part of the ribbon. The radula of neopilinid monoplacophorans is very similar to The second and third laterals of V. -
Cambrian Cephalopods
BULLETIN 40 Cambrian Cephalopods BY ROUSSEAU H. FLOWER 1954 STATE BUREAU OF MINES AND MINERAL RESOURCES NEW MEXICO INSTITUTE OF MINING & TECHNOLOGY CAMPUS STATION SOCORRO, NEW MEXICO NEW MEXICO INSTITUTE OF MINING & TECHNOLOGY E. J. Workman, President STATE BUREAU OF MINES AND MINERAL RESOURCES Eugene Callaghan, Director THE REGENTS MEMBERS Ex OFFICIO The Honorable Edwin L. Mechem ...................... Governor of New Mexico Tom Wiley ......................................... Superintendent of Public Instruction APPOINTED MEMBERS Robert W. Botts ...................................................................... Albuquerque Holm 0. Bursum, Jr. ....................................................................... Socorro Thomas M. Cramer ........................................................................ Carlsbad Frank C. DiLuzio ..................................................................... Los Alamos A. A. Kemnitz ................................................................................... Hobbs Contents Page ABSTRACT ...................................................................................................... 1 FOREWORD ................................................................................................... 2 ACKNOWLEDGMENTS ............................................................................. 3 PREVIOUS REPORTS OF CAMBRIAN CEPHALOPODS ................ 4 ADEQUATELY KNOWN CAMBRIAN CEPHALOPODS, with a revision of the Plectronoceratidae ..........................................................7 -
Phylum MOLLUSCA Chitons, Bivalves, Sea Snails, Sea Slugs, Octopus, Squid, Tusk Shell
Phylum MOLLUSCA Chitons, bivalves, sea snails, sea slugs, octopus, squid, tusk shell Bruce Marshall, Steve O’Shea with additional input for squid from Neil Bagley, Peter McMillan, Reyn Naylor, Darren Stevens, Di Tracey Phylum Aplacophora In New Zealand, these are worm-like molluscs found in sandy mud. There is no shell. The tiny MOLLUSCA solenogasters have bristle-like spicules over Chitons, bivalves, sea snails, sea almost the whole body, a groove on the underside of the body, and no gills. The more worm-like slugs, octopus, squid, tusk shells caudofoveates have a groove and fewer spicules but have gills. There are 10 species, 8 undescribed. The mollusca is the second most speciose animal Bivalvia phylum in the sea after Arthropoda. The phylum Clams, mussels, oysters, scallops, etc. The shell is name is taken from the Latin (molluscus, soft), in two halves (valves) connected by a ligament and referring to the soft bodies of these creatures, but hinge and anterior and posterior adductor muscles. most species have some kind of protective shell Gills are well-developed and there is no radula. and hence are called shellfish. Some, like sea There are 680 species, 231 undescribed. slugs, have no shell at all. Most molluscs also have a strap-like ribbon of minute teeth — the Scaphopoda radula — inside the mouth, but this characteristic Tusk shells. The body and head are reduced but Molluscan feature is lacking in clams (bivalves) and there is a foot that is used for burrowing in soft some deep-sea finned octopuses. A significant part sediments. The shell is open at both ends, with of the body is muscular, like the adductor muscles the narrow tip just above the sediment surface for and foot of clams and scallops, the head-foot of respiration. -
Shell Microstructures in Early Cambrian Molluscs
Shell microstructures in Early Cambrian molluscs ARTEM KOUCHINSKY Kouchinsky, A. 2000. Shell microstructures in Early Cambrian molluscs. - Acta Palaeontologica Polonica 45,2, 119-150. The affinities of a considerable part of the earliest skeletal fossils are problematical, but investigation of their microstructures may be useful for understanding biomineralization mechanisms in early metazoans and helpful for their taxonomy. The skeletons of Early Cambrian mollusc-like organisms increased by marginal secretion of new growth lamel- lae or sclerites, the recognized basal elements of which were fibers of apparently aragon- ite. The juvenile part of some composite shells consisted of needle-like sclerites; the adult part was built of hollow leaf-like sclerites. A layer of mineralized prism-like units (low aragonitic prisms or flattened spherulites) surrounded by an organic matrix possibly existed in most of the shells with continuous walls. The distribution of initial points of the prism-like units on a periostracurn-like sheet and their growth rate were mostly regular. The units may be replicated on the surface of internal molds as shallow concave poly- gons, which may contain a more or less well-expressed tubercle in their center. Tubercles are often not enclosed in concave polygons and may co-occur with other types of tex- tures. Convex polygons seem to have resulted from decalcification of prism-like units. They do not co-occur with tubercles. The latter are interpreted as casts of pore channels in the wall possibly playing a role in biomineralization or pits serving as attachment sites of groups of mantle cells. Casts of fibers and/or lamellar units may overlap a polygonal tex- ture or occur without it. -
By C. M. Yonge, D.Se. University of Bristol
453 EVOLUTION OF CILIARY FEEDING IN THE PROSOBRANCHIA, WITH AN ACCOUNT OF FEEDING IN GAPULUS UNGAR/GUS By C. M. Yonge, D.Se. University of Bristol (Text-figs. 1-6) CONTENTS PAGE Introduction 453 Rejection Currents in the Mantle Cavity of the Prosobranchia 453 Evolution of Ciliary Feeding 455 Vermetus novae-hollandiae . 456 Crepidula fornicata and other Calyptraeidae 457 Capulus ungaricus 459 Modification of gill filaments 461 Discussion. 465 Summary 467 References. 468 INTRODUCTION Ciliary feeding, of such widespread occurrence in the Lamellibranchia, is confined in the Gastropoda to a few scattered groups. In freshwater Pul- monata, such as Limnaea, cilia on the foot assist in feeding when the animal is creeping suspended from the surface film (Brockmeier, 1898). Thecoso- matous Pteropoda feed exclusively by the aid of cilia on the unpaired middle lobe and the paired side lobes of the foot, and an evolutionary series- Cavolinia-Cymbulia-Gleba-can be traced in which there is a progressive elaboration in the perfection of this mechanism and an accompanying reduc- tion in the buccal mass and associated structures handed down from carni- vorous ancestors (Yonge, 1926). Only in the few prosobranchs which have acquired ciliary feeding mechanisms do these represent a modification of the ctenidia as in the Lamellibranchia. They also, as it is the aim of this paper to show, represent a modification of the rejection currents present in the mantle cavity of typical prosobranchs. REJECTION CURRENTS IN THE MANTLE CAVITY OF THE PROSOBRANCHIA In typical Prosobranchia a respiratory current, created by the beating of the lateral cilia on the gill filaments, is drawn into the mantle cavity by way of the inhalent opening (frequently prolonged into a siphon, e.g. -
Givetian Brachiopods from the Trois-Fontaines Formation (Belgium, Dinant Synclinorium)
bulletin de l'institut royal des sciences naturelles de belgique sciences de la terre, 75: 5-23, 2005 bulletin van het koninklijk belgisch instituut voor natuurwetenschappen aardwetenschappen, 75: 5-23, 2005 Givetian brachiopods from the Trois-Fontaines Formation at Marenne (Belgium, Dinant Synclinorium) by Jacques GODEFROID & Bernard MOTTEQUIN Godefroid, J. & Mottequin. B„ 2005. — Givetian brachiopods from sisting of five units (thickness of these units from the base the Trois-Fontaines Formation at Marenne (Belgium, Dinant Syncli¬ to the norium). Bulletin de l'Institut royal des Sciences naturelles de Belgi¬ top: 26 m, 11 m, 23 m, 3.2 m, 23 m) (Fig. 3). The que, Sciences de la Terre, 75: 5-23, 2 pis., 9 figs., 4 tables, Bruxelles- brachiopods described herein have been collected Brussel, March 31, 2005 - ISSN 0374-6291. in the dark, well-bedded and bioclastic limestones with silty and crinoidal levels (unit 1), in the fine, dark co- loured, well-bedded limestones (unit 3) and in the crinoi¬ Abstract dal limestones rich in Scoliopora (unit 4). In units 1 and 3, although some beds are very rich in The brachiopods sampled from the Trois-Fontaines Formation in the brachiopods (some of them very large), it is difficult to Marenne quarry are mainly represented by two species: Spinatrypina sample well-preserved material and present the complete (Spinatrypina) fontis n. sp. and Eifyris socia n. sp. Orthid, rhyncho- inventory of the fauna. On the other hand, in unit 4, nellid, spiriferid and terebratulid brachiopods are also present but much rarer. Among them a new species, Bornhardtina equitis n. -
Guide to Fossil C911ecting
Educational Series - 1 ISSN 0544-3083 Guide to Fossil C911ecting ~~1. I ~l in/~~;/~_ Minnesota Minnesota Geological Survey Guide To FossIl Collecting In Minnesota R. K. Hogberg, R. E. Sloan and Sarah Tufford First edition 1965: revised edition 1967: reprinted 1979: reprinted 1985 ISSN 0544-3083 Geologic Time Chart_Minnesota Time Era Period Events in Minnesota Characteristic Life Quaternary 20 ENO· .ofMommals ZOIC 40 Tertiary No record in Minnesota ~ 60 M Sea enters Minnesota from E Cretaceous 100 S West. Deposition of sediments. 0 Z A~ of R.ptil.s 0 Jurassic I No record in Minnesota C Triassic k 200 Permian Ag.of Pennsylvanian No record in Minnesota Amphibians ..~ Mississippian ~ ~ ~ P Sea enters Minnesota from 300 Devonian "-() South. Deposition of sediments. .. A .~ L ~ . Silurian No record in Minnesota Ag. of Corals E 0 • of Straight 400 Ordovician Seas cover Minnesota at intervals. Z c_~ 0 I C Cambrian Deposition of sediments. A~ of Trilobit.s ~ Lava flows and deposition of sediments. PRECAMBRIAN Deposition of iron-rich sediments. First r.cord oIl,f. 4 \12 billion years lang Formation of mountains and igneous intrusions. Guide To FOSJt'l Colletting In Minnesota FoSSILS tell us what life was like on earth in ancient geologic time. A fossil clam, for example, lived on a sea bottom much as its modern relatives do. By finding many fossil clams, we can deter mine the extent of a prehistoric sea. Fossils also indicate the climates of the geologic past. Fossils show us that life on earth has not always been the same. In fact primitive algae and bacteria have given rise to reptile s, mammals, and finally to man. -
Biodiversity, Distribution and Patterns of Extinction of the Last Odontopleuroid Trilobites During the Devonian (Givetian, Frasnian)
Geol. Mag. 144 (5), 2007, pp. 777–796. c 2007 Cambridge University Press 777 doi:10.1017/S0016756807003779 First published online 13 August 2007 Printed in the United Kingdom Biodiversity, distribution and patterns of extinction of the last odontopleuroid trilobites during the Devonian (Givetian, Frasnian) ∗ RAIMUND FEIST & KENNETH J. MCNAMARA† ∗Laboratoire de Paleontologie,´ Institut des Sciences de l’Evolution, Universite´ Montpellier II, Cc 062, Place E. Bataillon, 34095 Montpellier, France †Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, UK (Received 18 September 2006; accepted 22 February 2007) Abstract – Biostratigraphical ranges and palaeogeographical distribution of mid-Givetian to end- Frasnian odontopleurids are investigated. The discovery of Leonaspis rhenohercynica sp. nov. in mid-Givetian strata extends this genus unexpectedly up to the late Middle Devonian. New material of Radiaspis radiata (Goldfuss, 1843) and the first koneprusiine in Britain, Koneprusia? sp., are described from the famous Lummaton shell-bed, Torquay, Devon. New taxa of Koneprusia, K. serrensis, K. aboussalamae, K. brevispina,andK. sp. A and K. sp. B are defined. Ceratocephala (Leonaspis) harborti Richter & Richter, 1926, is revised and reassigned to Gondwanaspis Feist, 2002. Two new species of Gondwanaspis, G. dracula and G. spinosa, plus three others left in open nomenclature, are described from the late Frasnian of Western Australia. A further species of Gondwanaspis, G. prisca, is described from the early Frasnian of Montagne Noire. Species of Gondwanaspis are shown to possess a number of paedomorphic features. A functional analysis suggests that, unlike other odontopleurids, Gondwanaspis actively fed and rested with the same cephalic orientation. The sole odontopleurid survivors of the severe terminal mid-Givetian biocrisis (‘Taghanic Event’) belong to the koneprusiine Koneprusia in the late Givetian and Frasnian, and, of cryptogenic origin, the acidaspidine Gondwanaspis in the Frasnian. -
Faunal Change and Bathymetric Diversity Gradient in Deep-Sea Prosobranchs from Northeastern Atlantic
Biodiversity and Conservation (2006) Ó Springer 2006 DOI 10.1007/s10531-005-1344-9 -1 Faunal change and bathymetric diversity gradient in deep-sea prosobranchs from Northeastern Atlantic CELIA OLABARRIA1,2 1Southampton Oceanography Centre, DEEPSEAS Benthic Biology Group, Empress Dock, South- ampton SO14 3ZH, United Kingdom; 2Present address: Departamento de Ecoloxı´a e Bioloxı´a Animal, Area Ecoloxı´a, Universidad de Vigo, Campus Lagoas-Marcosende, 36310 Vigo (Pontevedra), Spain (e-mail: [email protected]; phone: +34-986-812587; fax: +34-986-812556) Received 6 January 2005; accepted in revised form 11 July 2005 Key words: Deep sea, Diversity, Faunal turnover, Northeastern Atlantic, Porcupine Abyssal Plain, Porcupine Seabight, Prosobranchs Abstract. Despite the plethora of studies, geographic patterns of diversity in deep sea remain subject of speculation. This study considers a large dataset to examine the faunal change and depth-diversity gradient of prosobranch molluscs in the Porcupine Seabight and adjacent Abyssal Plain (NE Atlantic). Rates of species succession (addition and loss) increased rapidly with increasing depth and indicated four possible areas of faunal turnover at about 700, 1600, 2800 and 4100 m. Depth was a significant predictor of diversity, explaining nearly a quarter the variance. There was a pattern of decreasing diversity downslope from 250 m to 1500–1600 m, followed by an increase to high values at about 4000 m and then again, a fall to 4915 m. Processes causing diversity patterns of prosobranchs in the Porcupine Seabight and adjacent Abyssal Plain are likely to differ in magnitude or type, from those operating in other Atlantic areas. Introduction An increasing focus for biodiversity research in the deep sea has been to test for the existence of large-scale gradients in the diversity of marine soft- sediment fauna in deep sea (e.g.